Evaluation of CoVid-19 infection among vaccinated and unvaccinated individuals using biochemical markers

The evaluation of infection rate for CoVid-19 cases among vaccinated and unvaccinated individuals using haematological parameters is of interest. Data such as age, gender, occupation, location, signs and symptoms, length of symptoms, date of sample collection and report generation, status of vaccinations, and outcome available in the database was used in this analysis. Ferritin levels, D-dimer values, CRP, troponin-1 levels and platelet count of each CoVid-19 patient were recorded and analysed. Data shows that maximum number of cases was reported during the second wave 143 (51.07%). The common age group affected was 31-40 years 28.56%. The common symptom identified was weakness in arms and legs among the unvaccinated group of CoVid-19 positive group. However, common symptom identified was fatigue (87%) among those who received only the first dose of CoVid vaccine. Nonetheless, the symptom identified was hair loss (68%) among those who received both the doses of CoVid vaccine. Thus, data shows that people do experience severe and life-threatening COVID-19 infection despite receiving the vaccination. Nonetheless, the infection is mild and very few individuals require hospitalization. No deaths are reported in the group that received the vaccination. This is in contrast to the unvaccinated group, which had a severe CoVid-19 infection with few deaths reported.


Background:
Coronavirus disease 2019 (COVID-19) is a highly contagious viral infection brought on by the SARS-CoV-2 coronavirus, which causes severe acute respiratory syndrome.More than 6 million people have died as a result of the terrible effects of COVID-19 ) and Covaxin (BBV152) were widely used in the mass vaccination programme in India.A break through Infection was defined as the detection of SARS-Cov-2 on RT-PCR assay performed 11 or more days after receipt of a second dose of CoVid-19 vaccine and if no explicit exposure or symptoms had been reported during the first 6 days.It is difficult to achieve sterilizing immunity with SARs-Cov-2 vaccination and protection is going to be reduced even upon vaccination with time [4].Therefore the main research questions for the researchers include studying CoVid-19 infections aresurrounded their timing, frequency, causes, severity and levels of Infectiousness.The answers to these questions matter for several reasons.First, identifying the frequency, severity and causes of infections may inform the choice of public health responses: watchful waiting may be appropriate of are markedly increase transmission rates.Identifying the range of clinical outcomes seen in infections and determining how severe they can be as well as which clinical and demographic individual characteristics are associated with a severe outcome, will indicate how information about vaccination history can be used in prognostic scores to identify who should receive priority for additional vaccination or treatments [5].To find out the occurrence of infections, it is important to compare the incidence rate of infections to the rate of non-infections in unvaccinated people who apart from their vaccination status, are similar to the vaccinated [6].This comparison provides an estimate of vaccine effectiveness.These vaccines have also been shown to reduce the incidence of asymptomatic infection and the associated infectivity.However, break through infections have emerged in some vaccine recipients.To that no correlate of protection from break through infection has been reported.Unpublished data from the open-label phase III clinical trial of the pfizer and modern mRNA vaccines compares infections during a period in July and August 2021 among individuals randomized to vaccination at the start of the trail versus those originally randomized to placebo who received the vaccine later, following unblinding.In each cases were more frequently in the earlier vaccination individuals, providing randomized evidence for waning vaccine efficacy.When taking into account of prior studies, the utilization of circulating biomarkers for the immune system and inflammation has been thought of as a prognostic indication in COVID-19-positive individuals.However, their diagnostic value has not been well investigated, and there is no information on the influence of haematological markers on CoVid-19 infection [7].Therefore, it is of interest to determine the infection rate among the CoVid-19 cases admitted in a tertiary care teaching hospital.We also compared the incidence of CoVid-19 infection among the vaccinated and unvaccinated individuals.We further compared the influence of haematological parameters in the individuals with infection with that of unvaccinated individuals.

Methodology: Settings:
It is a retrospective study conducted on 381 patients, both IP and OP, who presented with COVID-19 symptoms in a Tertiary Care hospital, Telangana out of 1000 reported cases.Informed consent was taken from each individual before the collection of swabs.The study was undertaken after obtaining approval from the Institutional Ethics Committee.

Study design, sampling and methodology:
All confirmed infections of SARS-COV-2 were recorded in the daily CoVid-19 confirmed cases database of PCR laboratory.This database contains individual level data of infected patient like age, gender, occupation, locality, signs and symptoms, duration of symptoms, date of sample collection and report generated results, vaccination status, outcome etc.We conducted a two years and 1 month longitudinal retrospective observational study starting from Oct 2020 to Nov 2022.It concerned all the CoVid-19 positive cases and both vaccinated (fully or partially vaccinated) and unvaccinated individuals over the study period.The inclusion criteria were all the fully, partially vaccinated and unvaccinated patients who tested positive for SARS-CoV-2 infection and those who tested negative for Sars-CoV2 were excluded in the study.Children under ten years old and patients unwilling to consent were also excluded from the study.Individuals with mental or psychiatric severe issues and those with active tuberculosis were not allowed to participate in the study.Further the CoVid-19 positive samples were screened based on the variants.
Throughout the hospitalization period, the ferritin levels of each CoVid-19 patient were noted.According to the manufacturer's instructions, serum ferritin was tested using the COBAS 6000 from Roche Diagnostics, Indianapolis, IN, USA with Chemiluminescence immunoassay (CLIA) method.Using a conventional F200 analyser, with immunofluorescence method used to measure D-dimer levels.Serum troponin I (TnI) levels were determined using a chemiluminescent immunoassay with an ADVIA Centaur XP system from Siemens Medical Solutions in Malvern, Pennsylvania, and serum CRP levels were determined based on the principle of latex agglutination.CBC SYSMEX XK -21N haematology analyser was used to analyse the platelet count using EDTA samples taken from the patients' peripheral venepunctures.The platelet trend was also examined.Data were entered into Microsoft Office 2019 Excel sheets (Microsoft® Corp., Redmond, USA) and analyzed using Statistical Package for Social Sciences (SPSS) version 24.0 (IBM Corp., NY, USA), The data were presented as percentages, means, and standard deviation.3 showed the results of CoVid Wave wise distribution of total vaccinated CoVid-19 positive cases (280) with respect to age.Among the data for three waves was compared the maximum number of cases were reported during the second wave 143 (51.07%).The common age group affected was 31-40 years 28.56%.Table 4 shows the results of CoVid Wave wise distribution of total unvaccinated CoVid-19 positive cases (101) with respect to age.Among the data for three waves was compared the maximum number of cases were reported during the second wave 48 (47.52%).The common age group affected was 41-50 years 28.7%.Among the vaccinated group (61.43%) and unvaccinated groups (58.42%), male prevalence was high in CoVid-19 positive cases (Table 5).Among the vaccinated group (61.78%) and unvaccinated groups (68.31%), more CoVid-19 positive cases (Table 6) were reported from rural areas.

Table 2
represents the age-wise distribution of unvaccinated positive CoVid-19 cases.The results revealed that maximum number of cases was reported from age group 41-50 years 28.71% and least number of cases was reported from >60 age group 4.95% among the 101 total cases of unvaccinated CoVid-19 positive group.Table

Table 7
depicted the symptoms wise distribution of unvaccinated, 1 st dose, 2 nd dose positive CoVid-19 cases.The most common symptom identified was weakness in arms and legs among the unvaccinated group of CoVid-19 positive group.Where as in those patients who received only first dose of CoVid vaccine, and the most common symptom identified was fatigue (87%) and those who received both the doses of CoVid vaccine, the most common symptom identified was hair loss (68%).

Table 3 :
CoVid wave wise distribution of vaccinated CoVid-19 positive cases with respect to age

Table 4 :
CoVid Wave wise distribution of unvaccinated CoVid-19 positive cases with respect to age

Table 5 :
Sex-wise distribution of vaccinated and unvaccinated positive CoVid-19 cases

Table 6 :
Residency wise distribution of vaccinated and unvaccinated positive CoVid-19 cases

Table 8 :
Influence of haematological parameters in CoVid-19 infected individuals of both vaccinated and unvaccinated group

Table 9 :
Hospitalization and mortality wise distribution of vaccinated and unvaccinated positive CoVid-19 cases It is difficult to achieve sterilizing immunity with SARs-Cov-2 vaccination and protection is going to be reduced even upon vaccination with time.Therefore, timing, frequency, causes, severity and levels of infection are key parameters.Maximum number of cases was reported from age group 31-40 years